Field
The described technology generally relates to an organic light-emitting diode display.
Description of the Related Technology
An organic light-emitting diode (OLED) includes two electrodes and an interposed organic light emitting layer. Electrons injected from a cathode electrode and holes injected from an anode electrode are bonded to each other in the organic light emitting layer to form excitons. Light is emitted when the excitons discharge energy.
The OLED display includes a matrix of pixels, thin film transistors and capacitors for driving the OLED in each pixel. The transistors typically includes a switching transistor and a driving transistor.
The driving transistor controls a driving current flowing to the OLED and stores a data voltage in the storage capacitor connected to a driving gate node of the driving transistor to be maintained during 1 frame. Accordingly, a driving current of a predetermined amount is supplied from the driving transistor to the OLED during 1 frame emission.
However, due to a parasitic capacitance formed between the driving gate node connected to the driving gate electrode of the driving transistor and the data line, the voltage change of the data line affects the voltage of the driving gate node of the driving transistor. The voltage change of the driving source electrode changes a driving current flowing to the OLED, and this phenomenon generates a horizontal line defect according to an OFF signal of a light emission control line overlapping the data line.
Also, to prevent luminance deviation depending on a kickback voltage deviation between the data lines, a predetermined load must be maintained in the data line by overlapping the data line and the driving voltage line. However, in the structure in which the driving voltage line and the data line are formed in the same layer, the driving voltage line and the data line do not overlap each other such that the predetermined load is not maintained in the data line, thereby generating a vertical line defect.
The above information disclosed in this Background section is only to enhance the understanding of the background of the disclosure, and therefore it can contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.